Question

The diagram below shows the layers of a rock having an ammonite:

Answer 1

Answer:

Fossil Z is younger than Fossil Y.

Explanation:

For any age-related questions in geology, we have to consider the basic principle of stratigraphy. According to which, sediment layers on top harbor younger fossils whereas layers on the bottom have older fossils. In the case given here, Fossil Z is younger because it is in the top layer and Fossil Y is in the middle layer. The other two options are completely wrong because Fossil Y cannot be older than Fossi X and likewise, Fossil Z doesn't exist in multiple periods rather it is present only once.